2005 Mitsubishi Montero Limited Technical Highlights

The 2005 Mitsubishi Montero Limited features a 3.8-liter, SOHC, 24-valve, V6 engine that produces 215 horsepower at 5500 rpm and 248 pound-feet of torque at 3250 rpm. The increased power, compared to the previous 3.5-liter unit, is the result of additional displacement that is exploited with the appropriate camshafts, a cold-air induction system, and a free-flowing, larger-volume exhaust system that combined help the engine spread its high-torque output over a wide rpm range. The Montero's V6 engine is specifically tuned for low-rpm torque, a strong launch feel from stoplights and more midrange passing power.

Throttle-by-wire controls provide Mitsubishi's flagship Montero with additional refinement. No longer governed by the mechanical tug of a cable, the electronically-controlled throttle is more responsive to peddle input and combines with traction-enhancing electronics to create the most capable Montero yet. Noted for its smooth, quiet performance, the Montero's V6 has a single accessory drive belt that works in conjunction with a lightweight crank pulley to reduce noise and vibration from ancillary components. The large cooling fan blades help increase airflow through the radiator at slower rpm for quiet operation.

ACCELERATOR PEDAL ASSEMBLY

The Montero's cast-iron, 60-degree V6 block serves as the basis of a sturdy, smooth-running engine that features four-bolt main bearing caps, a crankshaft support girdle, radiused crank journals and a structurally supportive aluminum oil pan that helps dampen noise. Liquid-filled motor mounts and a cast-aluminum oil sump are designed to absorb sound and vibration, while the alloy pan structure reflects less noise from the bottom of the engine. Atop the short block rest a pair of aluminum, SOHC cylinder heads with four valves per cylinder.

TRANSMISSION

The Montero's automatic transmission makes use of oil-to-water cooling and a host of advanced engineering features. The Montero relies on a five-speed automatic transmission that features the latest in electronic tuning and computer control. Fully integrated with the engine's electronic control unit, the transmission's ECU has the dual benefits of the Mitsubishi Adaptive Shift Control and engine torque management.

The Montero's five-speed Sportronic(TM) transmission relies on Adaptive Shift Control for "learned control" of the shifting actions that helps tailor shifts to each driver's individual style. For a relaxed driving style, the transmission will shift at lower engine speeds, resulting in smooth, quiet operation and improved fuel economy. During more spirited driving, the transmission will shift at higher engine speeds, improving responsiveness and acceleration. Adaptive Shift Control is particularly helpful when hauling large loads or off-roading.

Additionally, the transmission will downshift for engine braking if the computer senses that the driver brakes frequently while descending a hill. The transmission also will hold a lower gear while climbing hills for more power and to prevent constant upshifting and downshifting.

Five-speed Sportronic(TM) Sequential Shift Transmission

The Montero driver not only has the benefit of five gears with lower ratios in first, second, third and fourth, but the shift selector can also be moved into the Sportronic(TM) gate to actuate gear selection manually. By shifting the lever forward or backward in the Sportronic(TM) gate, the automatic transmission will upshift or downshift through the five speeds at the driver's command.

In Sportronic(TM) mode, the driver can rev the engine to redline without allowing the transmission to upshift. If the driver does not upshift and the transmission reaches the rpm redline, fuel cutoff will intervene, but the transmission remains in the selected gear. Sportronic(TM) is programmed to override the driver's command in only one circumstance: if the gearbox is not downshifted to first gear upon stopping the vehicle, the transmission will automatically select first gear. In slippery conditions, the transmission can be manually shifted into second gear at rest for a more gradual takeoff.

Sportronic(TM) gives drivers a greater sense of control for mountain driving, trailer towing or fast-moving urban traffic. But unlike a manual transmission, drivers don't have to lift off the gas when changing gears, allowing for uninterrupted shifts.

Montero ActiveTrac(TM) 4WD System

Mitsubishi's internationally proven ActiveTrac(TM) Four-Wheel Drive (4WD) system is standard. Drivers have the choice of rear-drive, full-time All-Wheel Drive (AWD), high-range 4WD with locked center differential or low-range 4WD with locked center differential. The 4WD shifter engages an electric motor that changes drive modes. Thus, shifting from 2WD to 4WD in the Montero is no more complicated than flipping a switch.

All-Wheel Drive Mode (AWD)

The Montero's default rear-wheel-drive mode is preferred in most driving conditions as it provides optimal performance. A driver may also engage the Montero's full-time AWD permanently if he or she wishes. AWD provides more than added wet weather traction; it gives drivers a predictable rear-drive handling bias. A viscous coupling unit in the center differential limits front-to-rear wheelspin when the vehicle is in AWD. As part of the AWD system, the Montero's transfer case has a planetary gear set with a rear-wheel-biased torque split. The Montero implements a 33/67 power split to improve AWD handling. With less power flowing to the front wheels, the vehicle is less likely to understeer when accelerating out of a turn.

Locking Center Differential

Shifting the ActiveTrac lever into the 4WD mode locks the Montero's center differential for the additional traction of a 50/50 front-to-rear power delivery that is helpful on slick surfaces. Shifting to low-range 4WD provides a nearly two-fold (1.00:1 to 1.90:1) multiplication of torque for low-speed crawling on extremely steep hills, and through deep snow or mud. Simply put, the viscous coupling center differential compensates for large differences in wheel speed. By combining the viscous coupling center differential with the electronic traction aids available on the 2004 Montero, Mitsubishi engineers have succeeded in creating the most off-road-capable edition of the Montero to date.

SUSPENSION

The Montero's four-wheel, fully independent suspension system uses front double wishbones with coil springs, and a rear independent multi-link, coil-spring design. With
each wheel working through its own suspension, rather than an interconnected axle between the wheels, each tire acts as an autonomous unit with the freedom to adapt to on-road or off-road surfaces. This means that if one tire hits a rock or pothole, the composure and directional stability of the opposite tire remains unaffected.

Aiding the Montero's dynamic behavior is front-suspension geometry with more negative caster for better straight-line stability. Coupled with less kingpin offset and lean angle, and less positive camber angle, the Montero's front tires have a more consistent and perpendicular relationship with the road.

The front and rear suspensions also have the benefit of separate subframes: a boxed structure in the front and an open-box structure with a tubular crossmember in the rear. Both subframes are extremely rigid platforms that provide a solid foundation for the suspension and steering, but in turn provide isolation from the vehicle's body in order to filter out road noise and surface harshness.

The Montero's long suspension travel helps improve ride quality and the SUV's capability of absorbing road irregularities. The tires and suspension have noticeably more room for movement - the ability to absorb large impacts without bottoming out the suspension and knocking the vehicle off course. The Montero's four-wheel independent suspension gives it a confident and dignified feel on rough surfaces, but it also makes this SUV significantly more comfortable and composed on pavement.

STEERING

The power-assisted, rack-and-pinion steering system takes advantage of the Montero's rigid chassis and precise suspension mounting points - as well as the advanced tread patterns and reduced weight of contemporary SUV tires. Because rack-and-pinion steering requires fewer steel joints and connecting arms, it provides a more direct link between the front wheels. This gives the driver a level of response more in character with the Montero's unit-body and independent suspension agility.

For a solid feel in rough terrain, the Montero's rack-and-pinion steering system uses a check valve in the high-pressure fluid inlet line of the power assist. If one of the front tires hits a large bump - causing the wheel to turn sharply - the check valve keeps hydraulic fluid from being forced back into the line and causing steering wheel kickback. The driver will notice helpful feedback, but a lack of "fight" in the steering wheel when negotiating rough terrain.

BRAKES, WHEELS & TIRES

The Montero employs large, ventilated four-wheel disc brakes that are designed to dissipate heat and resist fade under hard use, heavy loads and high-speed driving conditions. The 2005 Montero also receives rugged yet stylish, new 17 x 7.5-inch multi-spoke alloy wheels with P265/65R17 mud and snow tires for traction in even the toughest conditions.

In front, twin-piston calipers effectively increase the mechanical "leverage" exerted on the brake pads. Twin-piston calipers have the advantage of providing better braking feel and more consistent modulation. The Montero uses electro-hydraulic brake assist rather than the more common vacuum assist. Integrated in one unit with the standard ABS, the electric motor that pressurizes the hydraulic fluid is highly "tunable," giving the brakes a more linear feel. Electro-hydraulic assist also helps reduce emergency response time-a major safety feature, when every microsecond counts.

Because the Montero's rear wheels do not share a common axle, both have their own ABS channel, rather than a single channel that acts on the rear wheels as a pair. The four-sensor, four-channel ABS means that each wheel can react independently to the traction available to that particular tire. The Montero also has an Electronic Brake force Distribution (EBD) system that takes advantage of the ABS solenoid valves and continuously adjusts the rear braking power. With a full load, EBD apportions more braking force to the rear wheels. Unloaded, EBD reduces rear-braking power and apportions more force to the front calipers.

The Montero's ABS is fully functional in all drive modes. Plus, emergency modulation of the brakes during panic stops is "customized" to compensate for different types of terrain. Particularly in 4WD or 4WD low-range, the ABS cycles more slowly so the tires don't "skate" on loose gravel or deep snow-terrains where a modest bit of wheel lock can actually reduce stopping distances.

The Montero relies on Mitsubishi's computer-controlled Active Skid and Traction Control (M-ASTC) to improve terrain-grabbing capability and handling on wet roads. The system relies on various sensors that determine the Montero's attitude relative to traction. The capabilities of the M-ASTC system have replaced multiple mechanical limited slip differentials and offer superior performance on dry, wet, rocky, severely inclined or jagged road surfaces, while improving road-holding capability and control on tarmac.

STRUCTURAL ENGINEERING

The Montero possesses an incredibly strong unitized body/chassis structure. CAD/CAM analysis allowed Mitsubishi Motors' SUV engineers to use the steel unibody itself as the vehicle's load-bearing member, creating a rigid, lightweight structure that features the latest developments in NVH and safety design. The Montero's steel unibody forms a sturdy architectural shell that relies on the strength of the fenders, engine compartment, roof pillars, roof panel, doorframes, and floor pan as structurally stressed members to add rigidity and strength to the vehicle. The body is an integral part of the safety engineering, performance technology and refinement strategy of the vehicle.

The body/chassis unit also is resistant to bending and torsional forces, enabling the suspension and steering to handle road undulations rather than compensating for frame movement.

SAFETY

The Montero's unibody provides occupant protection with front and rear crumple zones, safety cage construction and comprehensive side-impact strength.

Highlights of the unit structure include single-piece bodyside-stampings, full-length bumper-to-bumper frame "rails" integrated with the floor pan, and boxed lower side sills that run parallel to the main frame rails and below the doors. Roof and side-impact strength is augmented with high-rigidity floor-to-roof pillars in the A, B, C and D positions, lateral reinforcements that include three crossmembers under the cabin, structural crossmembers behind the bumpers, and a rolled-steel bar that connects the base of the A-pillars.

Side-impact strength is further increased with rolled steel beams connected to the inner door frames and oversized anchors that are in turn integrated with reinforced hinge mounts. Inside the front fenders, large three-dimensional structures run from the front of the wheel well to the leading edge of the firewall and A-pillars. Made of high-tensile-strength steel plating, these structural forms help control side-impact and frontal-crash energy, while also providing a sturdy locating mount for the front coil springs.

In the event of a severe frontal collision, the Montero's steering column collapses from the front of the vehicle rearward, reducing chances that the column will be forced into the cabin.

In a similar fashion, the reinforced carbon fiber driveshaft is designed to collapse in the event of major frontal impact, allowing the drivetrain to absorb the impact and disperse energy in a highly controlled manner.

The Montero is equipped with front and front seat-mounted side impact airbag inflatable Supplemental Restraint System (SRS). In addition, driver and passenger seatbelt pretensioners are designed to tighten the seatbelt, allowing the seatbelt to provide effective restraint much quicker. The pretensioners work in conjunction with the seatbelt force limiters, which gradually ease pressure on the shoulder belt during an impact situation once a pre-determined load is reached.

WARRANTY AND MANUFACTURING

As part of Mitsubishi Motors "Best-Backed Car" program, all models are backed by a comprehensive new vehicle limited warranty that covers the vehicle from bumper-to-bumper for five-years/60,000 miles. In addition, the powertrain is covered by a 10-year/100,000 mile limited warranty, while body panels have a seven-year/100,000 mile anti-corrosion/perforation limited warranty. The "Best-Backed Car" program also includes 24-hour emergency roadside assistance with free towing to the nearest authorized Mitsubishi retailer for warranty-related repairs for five years/unlimited miles.

Mitsubishi Motors North America, Inc., (MMNA) is responsible for all manufacturing, finance, sales, marketing, research and development operations of Mitsubishi Motors Corporation in the United States and Canada. Mitsubishi Motors sells coupes, convertibles, sedans and sport utility vehicles through a network of approximately 650 dealers. For more information, contact the Mitsubishi Motors News Bureau at (888) 560-6672 or visit media.mitsubishicars.com.